1. Field of the Invention
The present invention relates generally to a composite molded product, a production process and an apparatus therefor. More specifically, the invention relates to a composite molded article to be used as interior parts of a vehicle or so forth, exterior parts of an acoustic instrument or so forth, in which a skin material and a base member are integrally molded, a production process thereof, and an apparatus therefor.
2. Description of the Related Art
Conventionally, as interior parts of a vehicle or so forth, such as a lining of a vehicular door, a rear parcel shelf and so forth, a composite molded products, in which skin materials and base members are molded integrally, have been widely used.
On the other hand, in the recent years, for the purpose of enhancement of acoustic effect in a vehicular cabin or so forth, speakers are arranged in various positions in the vehicular cabin. In such a case, it is typical to preliminarily form an opening in the lining or so forth at a corresponding position to a speaker position and to fit a separately formed speaker cover or a speaker grill within the opening in order to affect for acoustic effect.
On example of a conventional rear parcel shelf is illustrated in FIGS. 10A and 10B. In FIG. 10A, a rear parcel shelf main body 100 is prepared as an intermediate product by bonding a skin material after molding a base body of a resin with openings 102 for acoustic speaker and an opening 104 for ventilation, or, in the alternative, by forming the openings 102 and 104 for the acoustic speaker and ventilation after molding the base body resin and the skin material simultaneously as a composite molded product. On the other hand, two speaker grills 106 and four ventilation grills (hereinafter referred to as "drafter grill") 108 are prepared separately and fixed in the openings 102 and 104 of the main body 100 by means of resin clips or so forth after engaging and positioning therein, for obtaining a finished product shown in FIG. 10B.
However, the method, in which the speaker grills and the drafter grills are formed separately from the rear parcel shelf main body, has no problem in the acoustic effect, but encounters a problem in complicatedness in color matching or so forth and in cost for requiring separate molding dies and so forth.
As a solution for the problems set forth above, there have been proposed technologies to perform formation of openings in the base member and integrally forming of the base member and the skin material, simultaneously, as disclosed in Japanese Patent Application Laid-Open Nos. Heisei 6-15671, Heisei 6-15672 and Heisei 6-15673.
Namely, the disclosed in the foregoing publications are directed to the molded product in which a base member formed with a through opening for passing a sound and a surface material are integrally molded in the form of including the through opening, or in the form of excluding the through opening, simultaneously.
However, in such a conventional skin material integrated composite molded product, when it is applied for a rear parcel shelf, the skin material is exposed over the entire surface of the base member. In this case, in order to assure sufficient strength required in view of durability for avoiding rupture and so forth by contacting with passengers, a diameter of the opening to be formed may be limited. On the other hand, for better propagation of acoustic vibration, it is preferred to have a greater opening ratio. In order to compromise these requirement, it becomes necessary to form a large number of small diameter openings.
For providing a large number of small diameter openings, it becomes inherent to provide forming pins and so forth in the number corresponding to number of openings to be formed. This makes forming dies complicate and results in high cost. Also, mold releasing characteristics is degraded to restrict material of the base member, board thickness and so forth.
Moreover, in the external appearance, at a portion corresponding to the speaker grill, only a flat skin material is present. As a result, there is no room for designing for obtaining a superior external appearance.